1. Field of the Invention
The present invention relates to a method for manufacturing an alignment layer, an active device array substrate and a color filter substrate, and more particularly to a method for manufacturing an alignment layer with better smoothness, an active device array substrate and a color filter substrate capable of enhancing the display quality of a liquid crystal display panel.
2. Description of the Related Art
Due to the progress of semiconductor devices and display devices, multimedia technology has become quite advanced. As far as the display is concerned, the liquid crystal display (LCD) with advantages such as having high resolution, high space-utilization efficiency, low power consumption, and being free of radiation, has gradually become the mainstream of the market. Generally, the liquid crystal panel is formed by two substrates and a liquid crystal layer sandwiched there-between. No matter whether an active matrix LCD or passive matrix LCD, an alignment layer is required to be provided on the two substrates, which is mainly used to align liquid crystal molecules to make them in a certain arrangement between the two substrates.
Generally, after completing a pixel array or a color filter array, an alignment layer is further formed on the pixel array or the color filter array. As for the medium or small substrate, the method for forming the alignment layer is utilizing the alignment layer coating technique (PI coater) to transfer the alignment material onto the surface of the substrate, then performing a curing process to form an alignment layer. However, as the substrate becomes increasingly large, if the alignment layer is manufactured through the alignment layer coating technique, the thickness for each region of the alignment layer is different, i.e., the accuracy of the layer thickness is poor. Also, manufacturing the alignment layer through the coating technique consumes a lot of alignment material, leading an increase of the manufacturing cost. Moreover, the table for coating the alignment layer has a relatively great volume and occupies a relatively large space.
In order to solve the above problems, an inkjet printing technique is developed, wherein the alignment material is sprayed and printed old the surface of the substrate, and an alignment layer is formed after the alignment material is diffused and cured. However, since the surface of the substrate itself is not smooth, the extent of diffusion for the alignment material at different regions is different, resulting in a poor smoothness of the alignment layer. Thus, the displaying quality of the liquid crystal display panel is influenced.